According to a recent study, the volume of plastic waste in our oceans may surpass that of fish by 2050 if nothing is done.

Plastic and rubbish pollute coral reefs as well as the world's oceans: Philippines, November 2011. / Keith A. Ellenbogen/ AP

The United Nations launched its first Ocean Conference in New York on Monday. In his opening address, Secretary-General Antonio Guterres called for protection of the oceans "to avoid long-term global catastrophe". Governments are planning to issue a call for action to reduce ocean pollution and to protect at least 10% of coastal and marine ecosystems by 2020.

The first step towards depollution is to stop throwing any more waste into the sea. Let us not forget that 80% of marine litter, both solid and liquid, macroscopic and microscopic, comes from rivers and coastal discharges.

The second step is to eradicate this pollution from all oceans and seas with a variety of techniques that depend on the size and type of the litter. Many of these have yet to be fully developed.

Several projects are already underway or being planned. For example, Dutchman Boyan Slat's Ocean Cleanup experiment was launched in June 2016. Its aim was to rid of plastic litter from the five big subtropical vortices or gyres.

Twenty kilometers from the Dutch coast, engineers have deployed one hundred meters of floats that are secured to the seabed and will remain in place for a year. From these floats, curtains 1.50 meters high are strung.

According to the inventor, this prototype should be capable of collecting up to 80 tons of plastic pieces and microparticles up to 1mm in diameter. The trial was undertaken by the Dutch government and the maritime services group Boskalis.

For the moment, however, we are still waiting for news of the outcome of this 1.5 million euro experiment.

Some oceanographers, such as François Galgani from the French Ifremer institute, have expressed reservations about the feasibility of this method in the middle of the ocean.

Collaboration between the University of Rennes and the company Oxxius may soon provide a laser-based method for detecting 0.2 mm microparticles at the water surface. The next issue will be how to collect the microparticles ingested by fish and eventually by humans as well.

Other projects are also underway. The German company Deurex has developed a synthetic wax that acts like a super-sponge to absorb oil spills in lakes, rivers, and seas.

Others, such as the Alteo company in Gardonne, Bouches-du-Rhône, have installed filter presses to purify the famous "red mud" from residues of bauxite that are rich in alumina and iron oxides.

Although these filters have reduced some of the pollution, toxic residues such as vanadium still remain. Authorities are thus forced to prohibit fishing near the source.

In addition, we still don't know how to filter waste water that is loaded with endocrine disrupters.

In conclusion, cleaning the oceans is theoretically, technically and politically possible but the work will take time.

In the meantime, it will be a lot more effective to establish rules such as the ban on selling plastic bags that France implemented in July 2016.

We need police forces to control and justice to sanction

Corinne Lepage, lawyer, President of COP 21, former Member of the European Parliament and Minister for the Environment.

There are international conventions in place, such as the 1982 Montego Bay Convention on the Law of the Sea, which contains a specific clause on pollution.

There are also specific conventions such as the 1969 International Convention on Civil Liability for Oil Pollution, which was renewed in 1992.

Also significant is the commitment in favor of oceans made by the United States at the Marrakech COP 22 Climate Change Conference last year.

A variety of documents exist. But what use are regulations if they are not complemented by an international marine police monitoring force or an international justice system that will enforce them?

The oceans cover a major part of the Earth's surface, and they play a critical role in our future in terms of food as well as climate change. Yet they remain the poor relation of international rights. It always comes back to the issue of governance of the high seas, which remain a law-free zone.

Some countries are trying to protect their territorial waters. France has successfully prevented oil spills at sea by monitoring its waters and tracing pollution to its source. Furthermore, it has maritime tribunals that impose heavy sanctions.

However, by doing this, they have simply displaced the oil spills to the open sea.

Too many ports are ill-equipped to collect used oil, while those that do so charge prices that dissuade ships [to dock].

Yet, when it comes to imposing virtuous practices, polluters, both at sea and on land, are always ready to raise the economic argument of distorting competition.

National laws requiring the establishment of plants to purify and treat toxic and dangerous products do exist. However, this does not prevent countries of the Global North from sending their waste into the Global South.

Apart from feeling exasperated that we have created a seventh continent made up of plastic waste, what can we do to go further?

We seem to be incapable of acting "upstream" on our production methods, e.g. by banning plastics. Therefore we need to act "downstream" by exerting control, imposing sanctions, setting up international coastguards and providing the necessary financial resources.

But even the European Union, which is sensitive to environmental issues, has never considered setting up an environmental coast-guard based on the model used to provide border security.

Even though climate issues, overfishing, and pollution have placed oceans at the forefront of discussion in recent years, there have been no definitive developments to protect them.

Newsletter

Get the latest from La Croix International. Sign up to receive our daily newsletter.

SUPPORT LA CROIX INTERNATIONAL’S COMMUNITY OF READERS

Support La Croix International's unique blend of international Catholic journalism by making it available to people in Asia and Africa who can't afford a subscription and often don't have credit cards to pay for it either.